Research And Implementation Of Electronic Seal System Based On PKI/CA

The electronical seal is used to realize the sign and seal function of traditional seal in electronical documents. It not only has feature of the documents’ authority, non-repudiation and makes documents not copied which traditional seal has, which also eliminates the safety defects of thetarditional seal, such as the illegible, information is unknown, not easy storage and so on, by advanced computer technology and information security technology. At the same time, the electronical seal also eliminates the e-commerce, the e-government document flow in the low efficiency which leads to the waste of time cost, promoting the paperless ffice, saving the management cost, improving office efficiency.The electronical seal technology is the effective way to protect the integrity, authentication and non-repudiation of the electronic documents. Its legal effect is equal to traditional signature or seal. Electronic seal’s visual effect conforms to China’s national conditions; the signed document alsa conforms to the traditional specification document format. Electronic seal system has very wide application prospect in the future. The system is based on the theory of cryptography, PKI (Public Key Infrastructure)/CA (Certificate Authentication), combined with the CAPICOM module technology, ActiveX technology and GDI+technology, it realize the electronic document seal, digital signature, signature verification, access control and other functions by ways of electronic signature, handwritten signature, keyboard notation.This paper mainly analysis, study and implement the electronic seal system, which based on PKI/CA system. First, the article deeply discuss and research the basic theories of encryption and decrypt technology, RSA algorithm, public key infrastructure (PKI), X.509protocol and so on. On the basis of the discussion and research, this paper analyzes the whole word process of the electronic signature system and put forward the design scheme of the system:which use CA as a third party authority, comprehensive use digital certificates, one-way hash function, digital signature technology and RSA algorithm to ensure the integrity, authentication and non-repudiation of the electronic documents, using the ActiveX control technology to realize the seamless integration with Word document to implement the research and development of the electronic seal system.